A new study has found that consistently losing just over an hour of sleep each night could contribute to gradual weight gain and increased sedentary behaviour, highlighting the important role quality sleep plays in maintaining overall health.
Researchers from Columbia University Irving Medical Center discovered that adults who slept about 78 minutes less than usual each night for six weeks gained nearly half a kilogram (around one pound) on average. Participants also became less physically active, spending more time sitting throughout the day. The findings were published in the Annals of Internal Medicine.
The study combined data from two randomized clinical trials involving 95 adults aged 20 years and older who were considered to be at increased risk of heart disease and metabolic disorders. Before the study began, participants typically slept at least seven hours per night.
During one phase of the research, participants maintained their normal sleep schedule. In another phase, they intentionally reduced their nightly sleep by about 78 minutes over a six-week period. Researchers then monitored changes in body weight, waist size, body composition, and daily activity levels.
The results showed that even moderate, long-term sleep restriction was associated with measurable increases in body weight and waist circumference. Participants also spent an average of 17 additional minutes each day being sedentary, suggesting that inadequate sleep may reduce motivation or energy for physical activity.
Health experts say sleep influences several hormones that regulate hunger and fullness. Not getting enough rest can increase levels of ghrelin, the hormone that stimulates appetite, while reducing leptin, which signals when the body is full. This imbalance may lead to increased calorie intake and a greater likelihood of weight gain over time.
Researchers believe the findings reinforce the importance of making adequate sleep part of a healthy lifestyle, alongside balanced nutrition and regular exercise. They suggest that healthcare providers should also consider sleep habits when advising patients about weight management and reducing the risk of obesity, type 2 diabetes, and cardiovascular disease.
Most health authorities recommend that adults aim for at least seven hours of quality sleep each night. Experts advise maintaining a consistent sleep schedule, limiting screen time before bed, reducing caffeine intake in the evening, and creating a comfortable sleep environment to improve sleep quality.
The researchers noted that while the weight gain observed during the study was modest, the cumulative effects of chronic sleep deprivation over months or years could significantly increase the risk of obesity and other long-term health conditions.
